Hot-air furnace



(NoModeL) v 8 H. GALLAHAN.

I HOT AIR FURNACE. No. 383,100. Patented May 22, 1888.

NITED STATES HENRY CALLAHAN,

OF DAYTON, OHIO.

HOT-AIR FURNACE.

SPECIFICATION forming part of Letters Patent No. 383,100. dated May 22, 1888.

Application filed November 16, 1887. Serial No. 255,347. (No model.)

To aZZ whom it may concern:

Be it known that I, HENRY UALLAHAN, of Dayton, in the county of Montgomery and State of Ohio, have invented certain new and useful Improvements in Hot-Air Furnaces, of which the following is a full, clear, and exact specification, such as will enable one skilled in the art to which my invention appertains to make and use the same.

The object of my invention is to produce a furnace having a large amount of heating-surface, which is at the same time very simple and easily constructed, and verydurable when in use.

The invention comprises a central portion having the usual firebox, a compartment for the products of combustion above said box, and transverse heating-tubes extending from side 00 side of said compartment. Around said central portion is formed an inclosure of suitable material in such manner as to leave be tween it and as much as possible of the radiating-surface of the central portion a hotair chamber. Cold air is introduced into this chamber, circulates about the central compartment, and is conducted therefrom for heating purposesin the usual manner. The transverse heating-tubes, however, are supplied with air independently of that which enters the h0t-air compartment in the usual way, by means of pipes which extend through the surrounding walls and are connected with the ends of said tubes. The air passed through these tubes is highly heated by the direct action of the products of combustion, and, passing from the farther ends of the tubes into the hot-air compartment, joins that body of air which is heated by the exterior of the furnace and is conducted away with it. The portion of the furnace im' mediately above the firebox is occupied by as many as possible of these transverse tubes, of which there are two sets, conducting air in opposite directions across the furnace, thus furnishing a large amount of heating-surface.

In order to make my invention clearly understood, I have shown in the accompanying drawings a means for carrying the same into effect.

In said drawings, Figure 1 represents ascotional perspective view of a hot-air furnace embodying my invention. Fig. 2 is a detail View illustrating the arrangement of the transverse pipes.

Referring to the drawings, I indicates the lower section or fire-box of the furnace, which may be of any usual or preferred construction. Above this firebox is situated the compartment G, through which the products of combustion pass. This central portion of the device is inclosed by the walls A, preferably of brick, as shown, forming around the fire-box and the upper compartment a hotair chamber, H. l

I indicates the cold-air duct, which communicates directly with the lower portion of the chamber H and supplies the same with air, which, after circulating through said chamber and around the central portion of the furnace, is conducted away for heating purposes by a suitable pipe or pipes, X. The smoke-pipe leads from the back of chamber G, and is not shown.

In the upper compartment, G, and at sufficient distance above the fire-box to prevent burning out, are situated a number of trans verse tubes, D, which in practice will be constructed of heavy wrought-iron and formed permanently with the casing of said compartment. The interior of said compartment is thus provided with a large extent of radiating and heating surface, which will receive the direct action of the products of combustion. These heating-tubes will be of very high temperature and capable of rapidly heating at one passage air which is of very low temperature when it enters the tubes. Each tube is supplied with an independent body of cold air by means of the separable pipe-sections E, of thin and durable metal-such as tin or galvanized iron-which pass through the walls A and connect with the ends of the tubes. The cold-air space or flue is formed upon each side of the furnace and practically across its whole lateral face by means of outer walls, O, which are situated at a distance from the walls A. The space B thus formed isinclosed at the top and at the front and back. The walls 0 are also, by preference, constructed of brick, though they may be much thinner than it is advisable to build the walls A. They may be connected with the walls Aby extending bricks across said space E and building them into each wall.

The fines B are supplied with cold air, preferably, as shown, from the same duct, I, that supplies the main hot-air chamber.

The furnace is one which, while very eii'ective for heating purposes, may be easily and cheaply constructed. The central portion, F, G, and D, will ordinarily be formed of heavy iron, and said parts permanently secured together. This central portion having been set up, the walls A are built around it, the pipesections E being added one after the other as the walls rise and being built securely into the same. Afurnace of large heating capacity may thus be constructed ina relatively small space.

Having thus described my invcntion,what I claim and desire to secure by Letters Patent of the United States is 1. In a hot-air furnace, the combination, with the firebox, of the compartment above the same, the walls A, inclosing the said firebox and compartment and forming a hot-air chamber, the outer cold-air flues, B, and the pipes D, extending from'said flues and diagonally upward throughsaid upper compartment and opening at a higher point into the hot-air chamber upon the opposite side of the furnace, substantially as set forth.

2. In a hot-air furnace, the combination of the fire-box, an upper compartment above said box, walls inclosing the fire-box and upper compartment and forming a hot-air chamber, the outer cold-air fines, the pipes extending through said upper compartment from one side to the other and opening into the hotair cham-' ber, and separable pipe-sections connecting the cold-air fines with the ends of the first-mentioned pipes, substantially as set forth.

3. In a hot-air furnace, the combination, with the fire-box and the upper compartment, ofthe walls A, inclosing said fire box and CODI- partment and forming a hot-air chamber, the outer walls, (1, forming with the first-mentioned walls cold-air fines, and pipes extending from said fines diagonally upward through the said upper compartment and to the hot-air chamber upon the opposite side of the furnace, sub stantially as set forth.

4. In a hotair furnace, the combination, with the fire-box and the compartment above the same, of the heavy heating-pipes B, extending across said compartment, the separable sections E, of light material, forming extensions of said pipes, the inclosing-Walls A, and the cold-air fines communicating with the outer ends of said sections, substantially as set forth.

. HENRY GALLAHAN.

Attcst:

\VARREN ll/IUNGER, GEORGE O. WARRINGTON. 

